diff --git a/upgrade_tests/upgrade_through_versions_test.py b/upgrade_tests/upgrade_through_versions_test.py
index a9aa0bc7b7..539cf9e76c 100644
--- a/upgrade_tests/upgrade_through_versions_test.py
+++ b/upgrade_tests/upgrade_through_versions_test.py
@@ -496,8 +496,10 @@ def upgrade_scenario(self, populate=True, create_schema=True, rolling=False, aft
                 self._check_values()
                 self._check_counters()
                 self._check_select_count()
-        self.cluster.nodelist()[0].nodetool("initializecms")
-            # run custom post-upgrade callables
+
+        if self.cluster.version() >= '5.1':
+            self.cluster.nodelist()[0].nodetool("initializecms")
+        # run custom post-upgrade callables
         for call in after_upgrade_call:
             call()
 
@@ -994,4 +996,4 @@ def create_upgrade_class(clsname, version_metas, protocol_version,
         [pair.starting_meta, pair.upgrade_meta],
         protocol_version=pair.starting_meta.max_proto_v,
         bootstrap_test=True
-    )
\ No newline at end of file
+    )